[Bf-blender-cvs] SVN commit: /data/svn/bf-blender [36378] trunk/blender/source/blender/ editors/transform/transform_constraints.c: fix [#27057] In cam perspective, world-axis-locked xform of an obj at cam loc fails

[Campbell Barton]

Revision: 36378
          http://projects.blender.org/scm/viewvc.php?view=rev&root=bf-blender&revision=36378
Author:   campbellbarton
Date:     2011-04-29 05:01:50 +0000 (Fri, 29 Apr 2011)
Log Message:
-----------
fix [#27057] In cam perspective, world-axis-locked xform of an obj at cam loc fails
when constraining the axis, ensure central point of the transformation is not too close to the view origin since this fails.

Modified Paths:
--------------
    trunk/blender/source/blender/editors/transform/transform_constraints.c

Modified: trunk/blender/source/blender/editors/transform/transform_constraints.c
===================================================================
--- trunk/blender/source/blender/editors/transform/transform_constraints.c	2011-04-29 04:43:36 UTC (rev 36377)
+++ trunk/blender/source/blender/editors/transform/transform_constraints.c	2011-04-29 05:01:50 UTC (rev 36378)
@@ -185,12 +185,44 @@
 	mul_m3_v3(t->con.mtx, vec);
 }
 
+static void viewAxisCorrectCenter(TransInfo *t, float t_con_center[3])
+{
+	if(t->spacetype == SPACE_VIEW3D) {
+		// View3D *v3d = t->sa->spacedata.first;
+		const float min_dist= 1.0f; // v3d->near;
+		float dir[3];
+		float l;
+
+		sub_v3_v3v3(dir, t_con_center, t->viewinv[3]);
+		if(dot_v3v3(dir, t->viewinv[2]) < 0.0f) {
+			negate_v3(dir);
+		}
+		project_v3_v3v3(dir, dir, t->viewinv[2]);
+
+		l= len_v3(dir);
+
+		if(l < min_dist) {
+			float diff[3];
+			normalize_v3_v3(diff, t->viewinv[2]);
+			mul_v3_fl(diff, min_dist - l);
+
+			sub_v3_v3(t_con_center, diff);
+		}
+	}
+}
+
 static void axisProjection(TransInfo *t, float axis[3], float in[3], float out[3]) {
 	float norm[3], vec[3], factor, angle;
+	float t_con_center[3];
 
 	if(in[0]==0.0f && in[1]==0.0f && in[2]==0.0f)
 		return;
 
+	copy_v3_v3(t_con_center, t->con.center);
+
+	/* checks for center being too close to the view center */
+	viewAxisCorrectCenter(t, t_con_center);
+	
 	angle = fabsf(angle_v3v3(axis, t->viewinv[2]));
 	if (angle > (float)M_PI / 2.0f) {
 		angle = (float)M_PI - angle;
@@ -217,13 +249,13 @@
 		float norm_center[3];
 		float plane[3];
 
-		getViewVector(t, t->con.center, norm_center);
+		getViewVector(t, t_con_center, norm_center);
 		cross_v3_v3v3(plane, norm_center, axis);
 
 		project_v3_v3v3(vec, in, plane);
 		sub_v3_v3v3(vec, in, vec);
 		
-		add_v3_v3v3(v, vec, t->con.center);
+		add_v3_v3v3(v, vec, t_con_center);
 		getViewVector(t, v, norm);
 
 		/* give arbitrary large value if projection is impossible */
@@ -236,14 +268,14 @@
 				mul_v3_fl(out, -1000000000.0f);
 			}
 		} else {
-			add_v3_v3v3(v2, t->con.center, axis);
+			add_v3_v3v3(v2, t_con_center, axis);
 			add_v3_v3v3(v4, v, norm);
 			
-			isect_line_line_v3(t->con.center, v2, v, v4, i1, i2);
+			isect_line_line_v3(t_con_center, v2, v, v4, i1, i2);
 			
 			sub_v3_v3v3(v, i2, v);
 	
-			sub_v3_v3v3(out, i1,  t->con.center);
+			sub_v3_v3v3(out, i1, t_con_center);
 
 			/* possible some values become nan when
 			 * viewpoint and object are both zero */